What is the best way to copy curve limits from one sequence to another?

In the sequence editor, on the left hand side under 'Step Templates', expand the Sequence Group.

Expand the sequence containing the Limits step that you wish to copy and drag the step into the desired location in the right hand side of the Sequence Editor. This action adds the step to your open sequence while maintaining all of its parameters from the original sequence.

Note: Only sequences in the current working folder are available in the Sequence Group. If the sequence containing the limits you wish to copy resides in another folder, you must either save your current sequence to that folder or drag the sequence of interest into your working folder.

Note: This works for all step types, and multiple steps can be selected and inserted at a time.